You can use the Joystick shield sits on top of your Arduino and turns it into a simple controller. 7 momentary push buttons and a two-axis thumb joystick gives your Arduino functionality on the level of old Nintendo controllers.

IBridge V1.0 is a 4X4 key-pad shield with a 5110 Graphic LCD interface.You can plug it on Arduino boards directly, and you can get the small development platform with keypad input and Graphic LCD display.